Interventions of Sodic Soil Reclamation Technologies ...

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Indian Res. J. Ext. Edu. 13 (1), January, 2013

Interventions of Sodic Soil Reclamation Technologies and Constraints in their Adoption Y.P. Singh1, U. C. Dubey2, Sudhir Singh3 and S. K. Dubey4 1. RVS Krishi Viswa Vidyalaya, KVK- ZARS, Morena, M.P., 2. KVK-CIAE, Bhopal, M. P., 3. KVK, Guna, M. P., 4. Regional Research Station, CSWCTR & TI, Chhalesar, Agra, U. P. Corresponding author e-mail: [email protected]

ABSTRACT On farm participatory trials were initiated in Galwa command area in North-Eastern part of Rajasthan state of India. The command area was severely affected by sodicity due to indiscriminate use of sodic ground water. Before initiation of trails, a survey was conducted to evaluate farmers’ response to land reclamation and to identify the constraints in adoption of reclamation technology. Out of 64 farmers surveyed, 34.4% knew the sodic soil reclamation technology, 44 farmers had not adopted any practice of sodic soil reclamation. Principal reasons of non-adoption of land reclamation was lack of availability of good quality water (27.3% farmers), while, other factors responsible for lack of response to technology were lack of risk bearing capacity, undulated topography, fragmented holdings, lack of investment power and knowledge of reclamation and limited availability of gypsum. After interventions for sodic soil reclamation, maximum and significantly higher mean yields of 4.69 t ha-1 grain and 5.07 t ha-1 stover of wheat and 2.61 t ha-1 grain and 11. 57 t ha-1 stover of pearlmillet was obtained with deep tillage in summer along with gypsum application @ 50% GR, green manuring and FYM @ 10 t ha-1 compare with other treatments, whereas non-significant difference was observed between deep tillage in summer along with gypsum application @ 25% GR, green manuring and FYM @ 10 t ha-1 and GR-50% along with green manuring and FYM @ 10 t ha1 treatment. Treatment of deep tillage in summer along with GR-50%, green manuring and FYM @ 10 t ha-1 resulted in maximum reduction of pH and soil sodicity, improvement in infiltration rate and increase in available N, P, K and micronutrients. Key words: Pearlmillet; Wheat; Sodic soil; Constraints of reclamation; Soil properties;

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alt affected soils are an important ecological entity in India and around 8.09 million ha is affected with menace of salinity in different climatic regions. Of this, 1.183 million ha area is in Rajasthan alone where soil reclamation programme is less effective as groundwater is of poor quality. As regards to underground water quality in Rajasthan state, only 16% is good, 16% marginal and 68% is of poor quality. Further, under poor quality water category, distribution of saline, sodic and saline sodic waters are about 16, 35 and 49%, respectively (Sen, 2003). Due to unavailability of good quality water for irrigation, use of poor quality underground water for irrigation has deteriorated the soil properties and reduced crop yields. Rajasthan state has developed several water projects for irrigation and drinking purposes. Galwa, Moti and Mansi dams for rain water conservation were developed in Tonk district.

These dams are used to supply irrigation water through canals at critical stages of crops. Expansion of irrigation facilities through inter-basin transfer of water has created problems in different command areas through out the country, either in the form of water-logging, or a combination of water-logging and salinity in different irrigation commands. Moreover, sodicity problem in command areas is created due to indiscriminate irrigation with sodic under-ground water, as several times canals fail to supply irrigation water when needed. Further, undulated topography, low rainfall and high evaporation rate have also contributed to salt accumulation, deterioration of soil condition and low crop-yields. It calls for management of such soils to improve their physico-chemical condition for attaining higher sustainable crop production in command areas. The present study of farmers’ participatory research was accordingly carried


to study the constraints on adoption and interventions of sodic soil reclamation technologies on pearlmillet - wheat crop sequence in canal command area. METHODOLOGY The study was carried out in Tonk district situated in Nouth-Eastern part of Rajasthan state of India located at 230 3’- 300 12’ N latitude and 690 30’- 780 17’ E longitude. On-farm trails were initiated in Galwa command area of Uniara panchayat samiti of Tonk district of Rajasthan. During the initial phase of the project, a survey was conducted on sixty four farmers of two selected villages to study their response to sodic soil reclamation and identify the constraints on adoption of reclamation technology. Simultaneously, soil samples were also collected and analyzed for physico-chemical properties. The soils of selected fields were deficient in organic carbon (1.9g kg-1), available N (147kg ha-1), P (10.39 kg ha-1) and Zn (0.44mg kg-1), but medium in available K (237kg ha-1). Available Cu, Fe and Mn contents were above the critical limit. Five representative farmers were selected for on farm participatory trials. The selected soil of farmers’ field was sandy loam in texture and classified as Ustifluvents. The selected interventions for soil reclamation were as follows: T1: farmer’s practice (control), T2: gypsum application as per gypsum requirement (GR) 25% + green manuring (GM), T3: GR-50% + GM, T4: GR-25% + GM + farm yard manure (FYM) @ 10 t ha-1, T5: GR-50% + GM + FYM @ 10 t ha-1, T6: deep tillage (DP) + GR-25% + GM + FYM @ 10 t ha-1 and T7: GR-50% + DP + GM + FYM @ 10 t ha-1. These seven interventions were applied only in first year from 28th June to 2nd July in five locations in randomized complete block design (RCBD). The experimental crop was wheat in Rabi

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season and pearlmillet grown in coming Kharif season. The experimental fields were divided in to seven sub plots, each having 500 m2 area with 0.30m high bunds for conservation of rain water. Before making plots, field-leveling and deep tillage up to 24 cm was done by using disc plough during last week of May to first week of June (summer season). The sesbania seed was sown after application of gypsum as per treatment. The gypsum requirement varied from 3.75 to 5.46 t ha-1 as per sodicity level. The recommended packages of practices were followed during all the years as given in Table 1. The sesbania crop for green manuring was incorporated in to soil by harrowing after 50 days. The total rainfall received during the experimentation period was 451 and 506 mm in 2006-07 and 2007-08, respectively. As per availability of irrigation water from canal, pre irrigation, crown root, tillering and booting stage irrigations were given by canal (good quality) water and only at milking stage, irrigation were given by under-ground (sodic) water during 2006-07, while during 2007-08 irrigation in wheat crop with canal water. The composition of sodic irrigation water had EC 0.67dS m-1, RSC - 9.0m.e. L-1, SAR - 14.7 and canal water EC - 0.25dS m-1, RSC - 0.80m.e. L-1, SAR - 0.92 was used for irrigation. After harvest of wheat crop, soil samples were taken from 0-0.30m soil layer with an auger 4 cm in diameter. The soil samples were air dried and ground to pass through a 2 mm sieve. Soil pH, electrical conductivity (1:2 soil water ratio) and exchangeable sodium of soil were determined by using pH meter, conductivity bridge and flame photometer, respectively. The exchangeable sodium percentage was determined as per Richards (1954). Organic carbon, available N, P, K and micronutrients were determined by Kjeltec-II

Table 1. Details of experimental operations Operation

Sesbania

Pearl millet

Wheat

Date of sowing Variety Line to line spacing (cm) Seed rate (kg ha-1) N application (kg ha-1) through urea P2O5 application (kg ha-1) through diammonium phosphate Zn application (kg ha-1) through Zinc sulphate Pre-sowing irrigation (70mm) Post-sowing irrigation (50mm) Date of harvest

June 28 to July 2, Local 15 40 Nil Nil Nil First monsoonal rain Rain fed 24-28th August*

July 2-7 HHB-67 20 20 60 60 First monsoonal rain Rain fed 1-9th October

Nov. 15-22 Raj-3765 15 100 90 60 05 01 4 6-12th April

* ploughing for green manuring by harrowing

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auto analyzer, Olsen P, NH4OAc-extractable K and DTPA extraction using atomic adsorption spectrophotometer (Jackson, 1973), respectively. Infiltration rate after harvest of wheat from each treatment in each year were measured in situ by double ring infiltrometer method and measurement of soil bulk density using core sampler (0.12 m diameter and 0.15 m length). RESULTS AND DISCUSSION Knowledge and constraints on adoption of sodic soil reclamation technology: Primary survey was conducted about knowledge and adoption of sodic soil reclamation technology by 64 farmers’ families of two selected villages of experimental area. The recommended practices of sodic soil reclamation were leveling of field, bunding for rain water conservation to facilitate leaching of salts, gypsum application @ 50% of gypsum requirement and green manuring. Out of 64 farmers in surveyed villages, about 14.1 per cent farmers used FYM for sodic soil reclamation, 9.4% field bunding for rain water conservation, 4.7% application of gypsum without knowing gypsum requirement and only 3.1 per Table 2. Prevailing practices of sodic soil reclamation adopted by farmers in the selected villages (N=64) Practices

No.

%

Rank

Application of farm yard manure Bunding for rain water conservation Applications of gypsum without knowing gypsum requirement Applications of gypsum without knowing gypsum requirement along with FYM and bunding of fields Did not know any practice

09 06 03

14.1 09.4 04.7

I II III

02

03.1

IV

44

68.8

V

Table 3. Constraint on adoption of sodic soil reclamation practices by farmers in the selected villages ( N=44) Component

No.

%

Rank

Lack of availability of good quality water Lack of risk bearing capacity Undulated topography Fragment holdings Lac of investment power Lack of knowledge of soil reclamation Limited availability of gypsum

12

27.3

I

10 07 06 04 03

22.7 15.9 13.6 09.1 06.8

II III IV V VI

02

04.6

VII

cent used gypsum without knowing gypsum requirement along with FYM and conserve rain water (Table 2). Out of 64 farmers, 44 farmers had not adopted any practice of sodic soil reclamation. Main reason of nonadoption of land reclamation as stated by 27.3 per cent farmers was lack of availability of good quality irrigation water, and have poor quality of underground water (Table 3). Other factors responsible for poor adoption were lack of risk bearing capacity, undulated topography, fragmented holdings, lack of investment power and knowledge of soil reclamation and limited availability of gypsum. Effect on yield: For sodic soil reclamation, application of gypsum as per GR @ 25% and 50% alone or in combination with green manuring, FYM @ 10 t ha-1 and deep tillage in summer were very effective and significantly improved the grain and stover yields of pearlmillet and wheat as compared to control (Table 4). Pooled yield indicated that the treatment of deep tillage in summer + GR-50% + green manuring and FYM @ 10 t ha-1 (T7) was the best treatment as the highest mean yields of 2.61 and 11.57 t ha-1 of grain and stover, respectively, of pearlmillet and 4.69 and 5.07 t ha-1 of grain and stover, respectively, of wheat Table 4. Response of levels of gypsum, deep tillage, green manuring and FYM on grain and stover yields of pearlmillet and wheat. Treat ment

Pearl millet yield

Wheat yield

(tonnes ha-1) 2007

(tonnes ha-1)

2008

Mean

2007

2008

Mean

1.05

0.91

0.98

1.55

1.46

1.51

(5.59)*

(3.49)

(4.54)

(1.97)

(2.29)

(2.13)

T2

1.72

1.82

1.77

2.97

3.20

3.09

(7.45)

(7.91)

(7.68)

(3.34)

(3.54)

(344)

T3

2.06

2.29

2.18

3.44

3.78

3.61

(9.06)

(9.39)

(9.23)

(3.90)

(4.29)

(4.10)

1.97

2.17

2.07

3.35

3.45

3.40

(8.65)

(8.89)

(8.77)

(3.87)

(3.91)

(3.89)

2.35

246

2.41

4.03

4.18

4.11

10.49)

(11.19) (10.84)

(4.41)

(4.60)

(4.51)

2.27 (10.10) 2.50 (11.20) 0.16 (1.05)

2.31 (10.65) 2.71 (11.93) 0.21 (1.19)

4.02 (4.55) 4.46 (5.01) 0.21 (0.46)

4.17 (4.68) 4.91 (5.12) 0.19 (0.38)

4.10 (4.62) 4.69 (5.07) -

T1

T4 T5 T6 T7 CD at 5%

*Stover yield

2.29 (10.38) 2.61 (11.57) -


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was recorded. The lowest mean yield of 0.98 and 4.54 t ha-1 of grain and stover, respectively, of pearlmillet and 1.51 and 2.13 t ha-1 of grain and stover, respectively, of wheat was recorded with farmer’s practice (T 1). The application of gypsum enhanced the availability of soluble calcium directly and indirectly through dissolution of native CaCO3. The calcium thus released displaced the Na+ from exchange complex and removal of soluble Na with anions (CO3= + HCO3-) through leaching reduced the pH of soil as well as improved the physicochemical properties of soil. Addition of organic manure improved the physicochemical environment in soil and consequently, greater extraction of water and nutrients by plants from the soil. These results are in conformity with findings of Singh et al., (2011) and Yaduvanshi and Sharma (2007). Non-significant difference was noticed between deep tillage in summer + GR-25% + green manuring + FYM @ 10 t ha-1 (T6) and GR-50% + green manuring and + FYM @ 10 t ha-1 (T5). Deep tillage was more effective in sandy loam soil which has low apparent field capacity and higher infiltration rate. Effect on physico-chemical properties: Application of gypsum @ 25% or 50% GR alone or in combination with GM, FYM and deep tillage in summer significantly reduced the pH and ESP and increased the available N, P, K and micronutrients (Table 5). Maximum reduction noticed in pH was 1.14, ESP 21, bulk density 0.05 Mg m-3, and increase in organic carbon was 0.4 g kg-1 soil, available N 72 kg ha-1, P 6.1 kg ha-1, K 69 kg ha-1, Zn 0.33 mg kg-1, Fe 0.7 mg kg-1, Cu 0.05 mg kg-1 and Mn 0.60 mg kg-1 with the treatment of deep tillage in summer along with GR-50%, green manuring and

FYM @ 10 t ha-1. Next highest reduction in pH was 0.92 and in ESP 19, bulk density 0.03 Mg m-3, and increase in organic carbon 0.3 g kg-1, available N 66 kg ha-1, P 4.7 kg ha-1, Zn 0.31 mg kg-1, Fe 0.6 mg kg-1, Cu 0.03 mg kg-1 and Mn 0.50 mg kg-1, under the treatment GR-50% along with green manuring and FYM @ 10 t ha-1 (T5) from control values of pH - 8.95, ESP - 32, organic carbon - 1.5g kg-1, bulk density - 1.51 Mg m-3, available N - 121 kg ha-1, P - 10.7 kg ha-1, K - 246 kg ha-1, Zn - 0.43 mg kg-1, Fe - 5.2 mg kg-1, Cu - 0.28 mg kg-1 and Mn - 2.0 mg kg-1, respectively. The treatment of deep tillage in summer along with GR-25%, green manuring and FYM @ 10 t ha-1 was as effective as T6. Application of gypsum as per GR and organic manure reduced soil sodicity, improved physico-chemical properties and consequently improved availability of nutrients in soil (Singh et al., 2011). Infiltration rate: At the end of Rabi crop during all the years, infiltration rate was measured in all the treatments (Table 5). The infiltration rate significantly increased with the application of gypsum @ 25% or 50% with green manuring only or along with FYM @ 10 t ha-1 and deep tillage in summer. Maximum infiltration rate 3.15 cm hr-1 was recorded with deep tillage in summer + GR-50% + green manuring + FYM @ 10t ha -1 followed by 2.85 cm hr-1 in the treatment of deep tillage in summer + GR-25% + green manuring + FYM @ 10 t ha-1 and 1.82 cm hr-1 with GR-50% + green manuring and FYM @ 10 t ha-1, respectively. The application of gypsum to sodic soil has been reported to improve aggregate stability and consequently the infiltration rate (Choudhary et al., 2006).

Table 5. Response of gypsum, deep tillage, green manuring and FYM on physico-chemical properties after harvest of wheat (2 year mean) Treatment T1 T2 T3 T4 T5 T6 T7 CD at 5%

EC (dS m-1)

pH

0.53 0.32 0.33 0.31 0.34 0.27 0.28 0.15

8.95 8.29 8.02 8.24 8.03 8.08 7.81 0.27

EC–electrical conductivity, IR–infiltration rate

ESP 32 20 16 17 13 14 11 1.5

OC (g kg-1)

BD (Mgm-3)

IR (cm hr-1)

N

P

Available nutrients K Zn Fe

Cu

Mn

1.5 1.9 1.4 1.7 1.8 1.8 1.9 0.1

1.51 1.50 1.48 1.49 1.48 1.46 1.46 0.03

0.32 1.06 1.23 1.65 1.82 2.85 3.15 0.20

121 150 173 164 187 184 193 21

10.7 12.7 13.4 13.5 15.4 14.9 16.8 1.5

246 278 286 290 294 290 315 26

0.28 0.28 0.29 0.30 0.31 0.31 0.33 0.01

2.0 2.2 2.3 2.3 2.5 2.4 2.6 0.15

ESP–exchangeable sodium percentage, N, P and K in kg ha-1

0.43 0.53 0.67 0.70 0.74 0.70 0.76 0.06

5.2 5.3 5.5 5.6 5.8 5.7 5.9 0.14

OC–organic carbon, BD–bulk density, Zn, Fe, Cu and Mn in mg kg-1

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CONCLUSION Primary survey indicated that only 34.4% farmers knew the recommended practices of sodic soil reclamation, whereas only 3.1% farmers used gypsum without knowing gypsum requirement along with application of FYM and did bunding of fields for rain water conservation, 4.7% used gypsum without knowing gypsum requirement, 9.4% did bunding of fields for rain water conservation and 14.1% used FYM. The grain and stover yields of pearlmillet and wheat was significantly improved by the addition of gypsum @ 25 and 50% GR with green manuring or along with FYM

and deep tillage in summer. Similarly, an increase in content of organic carbon, available N, P, K and micronutrients, and a decrease in pH, ESP and bulk density of the soils was observed. Maximum grain and stover yield of pearlmillet and wheat was obtained with deep tillage in summer along with gypsum application @ 50% GR + green manuring + FYM @ 10 t ha-1 followed by non-significant difference was noticed between GR-50% + GM + FYM @ 10 t ha-1 and deep tillage in summer along with gypsum application @ 25% GR + green manuring + FYM @ 10 t ha-1. Paper received on Accepted on

: :

February 03, 2013 February 27, 2013

REFERENCES Choudhary, O.P,; Ghuman, B.S,; Josan, A.S,; Bajwa, M.S. (2006). Effect of alternating irrigation with sodic and non-sodic waters on soil properties and sunflower yield. Agric. Water Manage, 85: 151-156. Jackson, M.L. (1973). Soil chemical analysis. Prentice Hall of India Pvt. Ltd., New Delhi. Richards, L.A. (Ed). (1954). Diagnosis and improvement of saline and alkali soil. USDA. Handbook No. 60. Sen, H. S. (2003). Problem soils in India and their management: Prospect and retrospect. J. Indian Soc. Soil Sci., 51 (4) : 388-408. Singh, Y.P.; Chauhan, S.V.S.; Singh, H.C.; Singh, S. (2011). Impact of sodic soil reclamation technology : An assessment of on farm trails. Indian Res. J. Ext. Edu., 11 (1) : 70-73. Yaduvansi, N.P.S.; Sharma, D.R. (2007). Use of wheat residue and manures to enhance nutrient availability and rice-wheat yield in sodic soil under sodic water irrigation. J. Indian Soc. Soil Sci., 55 (3) : 330-334.

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